Protein tyrosine kinases description

Additional information <1, 2> (this group of enzymes is under review by NC-IUBMB, recommendation for a nomenclature system based on acceptor amino acid specificity rather than on protein substrate. In accordance with this system protein-tyrosine kinases would belong to EC 2.7.1 l.X, <1,2> [1] The present data set is restricted to a literature review and does not contain a complete description of kinases. Classification system based on kinase domain phylogeny revealing families of enzymes with related substrate specificities, <1,2> [3]) [1, 3]... 

P2 and ALBP have tyrosine at position 19 (helix al). As will be described in the next section, phosphorylation by tyrosyl kinases occurs at this position. In terms of structure/function relationships, the phosphorylation of Tyr-19 is difficult to explain. If we assume a static picture for the protein as derived from the crystal structure, the tyrosine is buried and inaccessible to the protein kinase. A more detailed description of Tyr-19 will be given in Section IX,B. 

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